Electric bread toaster switch



Nov. 30, 1954 H. 1.. OLSON ET AL ELECTRIC BREAD TOASTER SWITCH 3Sheets-Sheet 1 Original Filed Feb. 4, 1950 awe/rm HENRY L. OLSON AND rHW J lllllllllllll v P fimim mm N ROBERT A. MILLER ATTORNEYS 1954 H.OLSON ETAL 2,695;935

ELECTRIC BREAD TOASTER SWITCH Original Filed Fb. 4, 1950 5 Sheets-Sheet2 FIGZ.

-1 am I I99 2|9 \M I: I, I 2 3 kl i 216 2| I 202 2:0 204 g G 2m 3M IHENRY L. OLSON AND ROBERT A. MILLER ATTORNEYS Nov. 30, 1954 H. OLSONETAL 2,695,935

ELECTRIC BREAD TOASTER SWITCH Original Filed Feb. 4, 1950 3 Sheets-Sheet3 232 226 233 333 208 223 2 49s y F5 "2" 2|6 2|3 2|? -205 224 9 5) G 2'8a I .2o| 2|92|o 203 203 HENRY L. OLSON AND ROBERT A. MILLER UnitedStates Patent ELECTRIC BREAD TOASTER. SWITCH Henry L. Olson and RobertA. Miller, Grand Haven, Mich, assignors to Caniiield. ManufacturingCompany, Grand.l'rltaven,.Mich., a. corporation of Michigan Originalapplication February 4, 1950, Serial No. 142,366, now Patent No.2,622,505, dated December 23,. 1952. Divided and this applicationlune10, 1950, Serial No. 167,418

8rClaims. (Cl. 200-67).

The herein disclosed invention relates to electric bread toasters andhas for an object to provide a bread toaster inswhiclr aswitchmechanismis used by means of which the switch contacts are positively heldclosed.

An object of the invention'resides in providing a construction utilizinga switch lever having a contact carrying arm and an actuating armand inaddition thereto an energizing arm'with a spring acting between saidarms-to give tothe switch lever snap action upon opening and closing ofthe switch.

Anzobject' of the invention resides in providing a construction in whichgreater force is exerted by the spring to'ho ld the. switchclosed thanopened.

Another object of the. invention resides in arranging the. axes ofthe-pivots for said switch lever and energizing arm' in. spaced parallelrelation and in making the energizing arm longer than the actuating armto cause the ends of the spring to travel along arcs of circlesgradually approaching one another'wherebygreater. pressure will beexerted by the spring to hold. the switch in closed position thaninopenposition.

Other objectsof the invention reside in the novel combinationandarrangement of partsand in the details of construction hereinafterillustratcdand/ or described.

In the drawings:

Fig, 1. isan elevational sectional view of a toaster'illustrating anembodiment of. the invention.

Fig. 2 is across sectionalview taken-on line 2'2 of Fig. 1.

Fig. 3 isa view similar to Fig. 2 showing the parts in altered position.

This-applicationisa division of the'copending application for patentofHenry L. Olson and Henry J. Freeze, Serial No. 142,366,.filed February=4, 1950, now Patent No..2,622,505, issuedDecember 23, 1952.

Forthe purpose=of illustrating the invention a portion of. an. electricbread toaster has been shown and which consists .of the usualtoastingamechanismzconfined within acase A. Withinthis case. isa frameB whichincludes anendframe member 33 and on which the. switch'mechanism. G of.the invention. is mounted. The toasting rnechanismdsoperated by. a lever88 pivoted to frame B. The switch mechanism. includes a switch leverpivoted for movement relativeto the frame in an up and down directionand having a. contact carrying arm and an actuating arm. On thecontactcarrying armis provided movable contacts adaptedto contact fixedcontacts carried by the frame. An energizing arm is pivoted for movementrelative to theframe about an axisparallel to the axis of the pivot forthe switch lever; The enerergizing arm has an end projecting outwardlybeyond the end of the short arm and which has a greater extent of travelthan the end of the. actuating arm. At the ends of said arms areprovided spring engagingmembers and between the same is an overcenter.spring which causes snap action of the switch lever when the energizingarm is moved. A link is connected to the operating lever of thetoasterand is also connected through a lost motion connection with saidenergizing arm. These various parts will now be described in detail.

The switch mechanism G of the invention is best shown in Figs. 1 and 2.This switch mechanism ineludes-a support 199 which is stamped from sheetmetal and which haslegs 200?projectingoutwardly. therefrom. These legsare attached to the end frame member 33 of the; toaster. and hold. the;support 199 spaced from said end frame member. The lowermost part ofthis support 199 has flanges 201 projecting outwardly therefrom andwhich have attached to them a bar 202 of insulating material. Rivets 203extend through these parts and hold the same attached. This bar'ofinsulating material carries two fixed contacts 204 and 205 which aremounted on screws 206 and 207- which are secured to said bar.Thesecontacts are connected in the circuit for the heating elements ofthe toaster in the usual manner. The contacts 204 and 205 lie in asubstantially horizontal plane. Pivoted' to the support 199 is a switchlever 208- constructed of insulating material. This lever is mountedon astud 209 secured to the support 199'and which forms the pivot meanstherefor. A clip 210 attached to the end of this stud holds the'saidlever in position thereon. The lever 208 has a long arm 211 which hasbeen referred to as a contact carrying arm and which has pivoted to itby means of a rivet 212 a swinging contact bar 213. This bar has ears214 extending upwardly therefrom and through which the rivet 212extends.The said contact bar is also formed with movable contacts 215 which whenthe lever 208 is swung in a clockwise direction engage the contacts 204and 205- and closes the circuit through the same. The lever 208'has atits other'end a short arm 216 which will be referred to as an actuatingarm and which is formed with a slot 217. In this slot is received oneend of a compression coil: spring 218, the other end of which encirclesa lug 219' formed on an arm 220. The end'of arm 216' adjacent said slotand-lug 219will be referred to as springengaging members; Arm 220 isformedat its end opposite the lug 219 with a U-shaped portion 221. Astud 222extendsthrough this portion and is attached tothe support 199;By means of'this construction the arm 220-is heldfrom twisting eventho-.thelug-219 is offset from said arm; Disposed adjacent the arm 220is a companion arm 223- which isattachedatone end to the arm 220 bymeans of a rivet 224. This arm. is straddled by the U-shaped portion'221of arm 220' and the-stud 222 passes through this armaswell as saidU-shaped portion. The arm 223 hence travels in unison with the arm 220;The axisof the-stud 222 is-parallel tothe axis of the stud-209; and bothare on'the'same side of a plane. containing thecontacts204-and205; thestud 209 being closer to saidplane than thestud 222. The distancebetweenthe lug 219-and theaxis of the stud 222 is greater thanthe'distance between the slot- 217 and the axis of the stud 209. Thiscausestheends of the spring 218 to travel along the arcs of two circlesindicated by the. reference numerals 240' and 241'. It will: be notedthat. these arcs approach each other at! their lower" ends. This causesthe spring 218to be more compressed at the lower position thereof shownin Fig. 3 thanin'its upper positionshown iuFig; 2. Consequently greaterpressure is exerted to hold the switchclosed than open. On the arm 223is formed a finger 225 which extends outwardly therefrom and which isadapted to engage the upper surface of. a. stop 226. Thisfinger limitsupward movement of. the end of the lever to. which spring 218 isattached. The. stop 226 is so situated that the upper surface of theswitch lever 208 strikes the lower surface of this stop. In this mannerthe, upward movement of the contact bar 213 is terminated. The stop 226is struck out-from the support 199 and is situated near the upperportion of the same.

The switch mechanism G is operated by the lever 88. This lever hasformed in it a key hole 227. Alink 228 is pivoted to said lever throughthishole. For the purpose, the said link at its upper end has an offset229 which is formed with a neck 230 and with a head 231 at. its outerend. The head 231 is insertable into the slot 227 by. holding said link.horizontal and when turned to a vertical position the neck 230 becomesseated in the circular part of said slot and'is pivotally attached tosaid lever. The lower end of the link has formed in it a slot 232. Astud 233 passes through this slot and is secured to the companion arm223. This slot provides a lost motion connection between the toasteroperating lever and switch mechanism whereby the toaster is notenergized until said lever approaches its lowermost position.

The operation, of the invention is as follows: The

parts are normally situated as illustrated in Fig. 2. When the lever 88is depressed the timing mechanism of the toaster is energized. The link228 travels downwardly with the lever 88 and when the stud 233 reachesthe upper end of slot 232 arm 220 is depressed. This causes the springengaging member 219 to travel in the arc of the circle indicated at 240.As the said spring engaging member passes a line connecting springengaging member 217 and stud 222 the lever 208 is rotated in a clockwisedirection and the contact bar 213 moves downwardly to bring the contacts215 in engagement with the contacts 204 and 205. This energizes theheating elements of the toaster. It will be noted that the are 240through which the spring engaging member 219 passes and the are 241through which the spring engaging member 217 passes approach each otherso that when the switch is in closing position the spring 218 iscompressed to a greater extent as shown in Fig. 3 than when the switchis in open position as shown in Fig. 2. Upon opening of the switch theoperation is exactly reversed.

The advantages of the invention are manifest. The switch is of the snapaction type whereby rapid opening and closing of the switch is madepossible to reduce arcing across the contacts. The switch is operated bythe operating lever so that the number of intervening parts is aminimum. In this manner the operation of the switch becomes positive.The entire switch is mounted on a single support permitting of easyassembly of the parts before installation of the switch on the toasterframework. Movement of the contacts occurs in the same direction as themovement of the operating portion of the operating lever. Due to thelost motion connection between the operating lever and switch mechanismthe switch is not actuated until the operating lever is near the end ofits travel, thereby preventing energization in the event that the breadis not well within the bread oven. By the arrangement of the pivots forthe moving parts of the switch and the lengths of the arms thereofgreater compression of the switch actuating spring occurs when theswitch is closed than when open. This causes increased pressure on thecontacts when the switch is constructed as disclosed than would bepossible with the conventional type of switch.

Changes in the specific form of the invention, as herein described, maybe made within the scope of what is claimed without departing from thespirit of the invention.

Having described the invention, what is claimed as new and desired to beprotected by Letters Patent is:

1. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever pivoted for movement relative tosaid frame and having an actuating arm and a contact carrying arm, afixed contact carried by said frame, a movable contact carried by saidcontact carrying arm and adapted to make contact with said fixedcontact, an energizing arm pivoted for movement relative to said frameabout an axis parallel to the axis of the pivot of said switch lever,said energizing arm having an end projecting outwardly beyond the end ofthe actuating arm of said switch lever and having a greater extent oftravel than the end of said actuating arm, an over-center spring actingbetween the ends of said arms, a stop fixed relative to said frame, afinger movable with said energizing arm and engageable with said stop tolimit movement thereof, said switch lever having a part engageable withsaid stop to limit movement of said switch lever into switch openingposition and a connection between said energizing arm and said operatingmember.

2. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever pivoted for movement relative tosaid frame and having an actuating arm and a contact carrying arm, fixedcontact carried by said frame, a movable contact carried by said contactcarrying arm and adapted to make contact with said fixed contact, anenergizing arm pivoted for movement relative to said frame about an axisparallel to the axis of the pivot of said switch lever, said energizingarm having an end projecting outwardly beyond the end of the actuatingarm of said switch lever and having a greater extent of travel than theend of said actuating arm, an overcenter spring acting between the endsof said arms, a stop fixed relative to said frame, a finger movable withsaid energizing arm and engageable with said stop on one side thereof tolimit movement thereof, said switch lever having a part engageable withsaid stop on the other 4 side thereof to limit movement of said switchlever into switch opening position and a connection between saidenergizing arm and said operating member.

3. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever pivoted for movement relative tosaid frame and having an actuating arm and a contact carrying arm, fixedcontact carried by said frame, a movable contact carried by said contactcarrying arm and adapted to make contact with said fixed contact, anenergizing arm having a U-shaped end, a stud fixed relative to saidframe and extending through said U-shaped end and restraining twistingof said arm, said energizing arm having an end projecting outwardlybeyond the end of the actuating arm of said switch lever and having agreater extent of travel than the end of said actuating arm, a springengaging member on the end of said energizing arm offset from saidenergizing arm, an overcenter spring acting between said spring engagingmember and said end of said actuating arm and a connection between saidenergizing arm and said operating member.

4. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever having a contact carrying arm andan actuating arm, pivot means therefor having an axis fixed relative tosaid frame, a fixed contact carried by said frame and a movable contactcarried by the contact carrying arm of said switch lever, an energizingarm, pivot means therefor having an axis fixed relative to said frameand parallel with and spaced from said first named axis, a springengaging member on said actuating arm, a spring engaging member on saidenergizing arm, a spring acting between said spring engaging members,and adapted when the spring engaging member on the actuating arm is toone side of a line passing through the other spring engaging member andthe axis of the switch lever to urge said lever to move the movablecontact into switch closing position and when on the other side of saidline to cause said movable contact to move into switch opening position,stops for limiting the movement of said switch arm to switch opening andswitch closing positions, said spring engaging members traveling througheccentric arcs of different radii approaching one another when theswitch arm is in closing position to cause the spring to exert a greaterpressure on the switch arm when the contacts are in switch closingposition than when in switch opening position and a connector betweensaid operating member and said energizing arm.

5. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever having a contact carrying arm andan actuating arm, pivot means therefor having an axis fixed relative tosaid frame, a fixed contact carried by said frame and a movable contactcarried by the contact carrying arm of said switch lever, an energizingarm, pivot means therefor having an axis fixed relative to said frameand parallel with and spaced from said first named axis, a springengaging member on said actuating arm, a spring engaging member on saidenergizing arm, a spring acting between said spring engaging members andadapted when the spring engaging member on the actuating arm is to oneside of a line passing through the other spring engaging member and theaxis of the switch lever to urge said lever to move the movable contactinto switch closing position and when on the other side of said line tocause said movable contact to move into switch opening position, stopsfor limiting the movement of said switch arm to switch opening andswitch closing positions. the distance between the axis of the pivot forthe actuating arm and the spring engaging member on said arm beinggreater than the distance between the axis of the pivot for theenergizing arm and the spring engaging member on said arm to cause saidspring engaging members to travel through eccentric arcs of differentradii approaching one another when the switch arm is in closing positionto cause the spring to exert a greater pressure on the switch arm whenthe contacts are in switch closing position than when in switch openingposition and a connector between said operating member and saidenergizing arm.

6. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever having a contact carrying arm andan actuating arm, pivot means therefor having a horizontal axis fixedrelative to said frame, a fixed contact carried by said frame anddisposed below said axis, and a movable contact carried by the contactcarrying arm of said switch lever, an energizing arm, pivot meanstherefor having an axis fixed relative to said frame and parallel withand spaced from said first named axis, said second named axis beingdisposed above and at a locality between the contacts and said firstnamed axis, a spring engaging member on said actuating arm, a springengaging member on said energizing arm, a spring acting between saidspring engaging members the distance between said first named springengaging member and the axis of the pivot of said actuating arm beingless than the distance between the second named spring engaging memberand the axis of the pivot for said energizing arm, to cause said springto exert a greater pressure on said contacts when the switch lever is incontact closing position than when in contact opening position and aconnector between said operating member and said energizing arm.

7. In combination a frame, an operating member guided for movementrelative to said frame, a switch lever having a contact carrying arm andan actuating arm, pivot means therefor having an axis fixed relative tosaid frame, fixed contacts carried by said frame and disposed in a planeparallel to the axis of said pivot means, movable contacts carried bysaid contact carrying arm and engageable with said fixed contacts, saidpivot means being disposed to one side of said contacts, an energizingarm, pivot means therefor having an axis fixed relative to said planeand spaced from and parallel to the axis of said first named pivotmeans, said second named axis being disposed more remotely from saidplane than said first named axis, spring engaging members on saidactuating arm and on said energizing arm, a spring acting between saidspring engaging members, the distance between the axis of the pivotmeans for the energizing arm and the spring engaging member thereonbeing greater than the distance between the axis of the pivot means forsaid switch lever and the spring engaging member thereon to cause saidspring to exert a greater pressure on said contacts when the switchlever is in contact closing position than when in contact openingposition and a connection between said operating member and said switchlever.

8. In combination, a support, a switch lever having a contact carryingarm and an actuating arm, pivot means therefor having an axis fixedrelative to said support, a fixed contact carried by said support and amovable contact carried by said contact carrying arm of said switchlever, an energizing arm, pivot means therefor having an axis fixedrelative to said support and parallel with and disposed in juxtapositionwith the axis of said first named pivot means, a spring engaging memberon said actuating arm, a spring engaging member on said energizing arm,a spring acting between said spring engaging members and when the partsare in one position urging the contacts apart and when in anotherposition urging the contacts into engagement, the distance between thespring engaging members on the energizing and actuating arms beingcloser together when the contacts are in engagement than when apart toincrease the spring pressure between the fixed contact and the movablecontact when in engagement.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,518,701 Penn Dec. 9, 1924 1,610,213 De Ville Dec. 7, 19262,237,705 Kohl Apr. 8, 1941 2,447,871 Riche Aug. 24, 1948 2,558,219 KohlJune 26, 1951 2,574,770 Zeller Nov. 13, 1951

